module.exports = {
  presets: [
    // https://github.com/vuejs/vue-cli/tree/master/packages/@vue/babel-preset-app
    "@vue/cli-plugin-babel/preset",
  ],
  env: {
    development: {
      // babel-plugin-dynamic-import-node plugin only does one thing by converting all import() to require().
      // This plugin can significantly increase the speed of hot updates, when you have a large number of pages.
      //@babel/plugin-proposal-optional-chaining : 支持在模版中使用 user?.name ?? 'Unknown' （对于可选链）
      //@babel/plugin-proposal-nullish-coalescing-operator 对于空值合并运算符
      plugins: [
        "dynamic-import-node",
        "@babel/plugin-proposal-optional-chaining",
        "@babel/plugin-proposal-nullish-coalescing-operator",
      ],
    },
  },
};
